Power transmission for bulldozers



June 2, 1 942. c. E Roi-IN 2,235,094

POWER TRANSMISSION FOR BULLDOZERS 7 Filed March 7, 1941 s Sheets-Sheet 2Inventor Patented June 2, 1942 ili li'ih' FFWE tier

2,285,094 PGWER TRANSMISSION FOR BULLDOZERS Charles Edwin Bonn,Sacramento, Calif., assignor of ninety per cent to Inez Rohn,Sacramento, Calif.

This invention appertains to new and useful improvements in powertransmission for bulldozers. I

The principal object of the present invention is to provide powertransmission means, includventional bulldozer blade can be lifted andlowered quickly and but with a minimum requirement of skill and efforton the part of the operator.

Another important object of the invention is to provide a powertransmission for bulldozers which is of simple construction, yet whereinthe parts are positive acting and unsusceptible to the ready developmentof defects.

These and various other important objects and advantages of theinvention will become apparent to the reader of the followingdescription.

In the drawings- Figure 1 represents a side elevational view of abulldozer apparatus showing the novel transmission in use.

Figure 2 is a top plan view of the structure shownin Figure 1.

Figure 3 is a rear elevational view of the structure shown in Figure 1.

Figure 4 is an enlarged fragmentary elevational view showing the clutchand associated means shown proportionately smaller in Figure 2.

Figure 5 is a sectional view through the transmission.

' ing a specially designed clutch, whereby the conq Figure 6 is afragmentary top plan view of the 2 transmission with parts broken away.

Referring to the drawings wherein like numerals designate like parts, itcan be seen that the numeral 5 generally refers to a caterpillar type oftractor which has side frame members 6.

Numeral I denotes a bulldozer blade provided with rearwardly extendinghollow channeled members 8 which telescope arms 9 and are securedthereto as at ID. The arms 9 are pivotally secured as at I I to blocksI2 on the rear portion of the frame 6.

Rising from each of the side frame members 6 is a post I3. A pair ofbeams I4, one at each side of the tractor 5 are suspended by legs I5from fulcrum points I 6 on the upper ends of the posts I3 and theforward ends of these beams I4 are connected by bars I! to hollowmembers 8.

The rear portions of the beams I4 are inclined as at l8 and bridged by abar I 9, on which is mounted a double pulley block 20. bar I9 and pulleyblock 20 are located above the power transmission generally referred toby numeral 2|.

The bridge This transmission 2| consists of a gear housing 22 having apower shaft 23 from the tractor engine extending into one end thereofand on this end of the shaft 23 and located within the housing 22 is agear 24 meshing with a second gear 25 also located in the housing 22 andcarried by a shaft 23, which extends rearwardly from the housing 22. Ahub 21 is splin'ed as at 28 to the intermediate portion of the shaft 26and this hub 21 carries a clutch annulus 29 having a laterally disposedand tapered circumferential portion 39 and internal fins 3! for guidingthe formation 39 properly into the clutch side 32 of a reel 33 on whicha cable 34 is wound. The clutch side 32 of the reel 33 has a taperedchannel 35 in the side thereof for receiving the tapered formation 30and on the peripheral portion of this side member 32 is a brake band 35.

-A plate 31 is diametrically disposed across the back side of the reel33 and is secured to a guard annulus 38 by bolts 39, this annulus 38being divided into a pair of semi-circular sections a.b. Interposedbetween the plate 31 and the corresponding end of the reel 33 is anabutment plate 40 held in place by bolts 4|, the latter also serving tohold a lubricating cap 42 over the corresponding end of the shaft 26.Thus the reel 33 is left free to rotate on the shaft 26 when the clutchformation 30 is disengaged from the clutch side 32 of the reel 33.

Plates 43, 44 extend from the ends of the plate 31 to connect to thecrankcase 45 of the tractor 5.

As shown in Figure 6, common operating means is provided for shiftingthe clutch collar 21 and operating the brake band 36 simultaneously. Inthis connection, a bracket 46 extends rearwardly from the gear case 22and a second bracket 41 extends obliquely in a forwardly direction fromthe plate 44. A control shaft 48 extends vertically through the brackets46 and 41 and carries a cam 49 which operates against the curved end 50of a rocker 5I which is rockably supported by a bracket 52 projectingforis interposed between the gear case 22 and the,

curved end 59 of the rocker 5! for the purpose of urging this end of therocker toward the cam 49 and maintaining the clutch formation 30disengaged from the reel side 32.

Also carried by the vertical control shaft 48 is a laterally disposedplate 59 on which rides a 65 is a coiled compression spring 19.Obviously,

the fact that the spring 10 can be controlled by regulating the nut 68on the pin 66.

As clearly shown in Figure 4, the plate 59 has an inclined portion ll onwhich the headed pin 60 can ride as well as on the plate 59.

As is apparent in Figures 1 and 3, a pulley 12 is secured to the crossplate 31. The cable 34 has one end anchored as at 13 (see Figure 4) toone side of the pulley block 12. From this anchored point the cableextends upwardly over one pulley of the block 20, then downwardly andunder the pulley of the block 12 and then upwardly over the remainingpulley of the block 20 and then downwardly to wind on the drum 33.

In the operation of the machine, the operator stands or has a seat onthe rear portion of the bulldozer and by operating the shaft 38 throughthe medium of a handle 14, he can actuate the cam 49 to swing the rocker5| in a manner to cause engagement of the clutch formation 30 with theclutch side portion 32 of the reel 33, to the end that power will betransmitted to the reel 33 and the bulldozer blade I lifted to thedesired point and by avery slight movement of the handle 74, the clutchmembers can be caused to slip. In otherwords, there is a slight playbetween positioning of the handle 14 for operating the clutch member 39and the position for operating the brake band 36 so that a slightplaying back and forth of the handle 14 will result in a gradual liftingor lowering of the bulldozer blade to the desired extent. t

While the foregoing specification sets forth the invention in specificterms, it is to be understood that numerous changes in the shape, sizeand materials may be resorted to without departing from the spirit andscope of the invention as claimed hereinafter.

Having described the claimed as new is:

In an apparatus of the class described, a driven reel shaft, a reelfreely rotatable on the reel shaft and embodying a driven clutch memberforming a brake drum, a driving clutch member splined on the drivenshaft for shifting into and from engagement with the driven clutchmember, a brake band trained around said drum and having opposed fixedand movable ends the movable end for drawing toward the fixed end totighten the band against said drum, and

invention, what is means to shift said driven clutch member intoengagement and tighten said band comprising a manually operative controlshaft rotatably mounted, a cam on said control shaft, a pivoted clutchshifting lever having one end operatively connected to said drivingclutch member to shift the same and a curved cam on its other endengaging said first cam, a cam plate fast on said control shaft andhaving a flat face and an adjoining inclined face, a band tightening armpivotally mounted adjacent the fixed end of the band and operativelyconnected to the movable end thereof, said arm extending across saidplate, and a ball mounted on said arm and riding on the plate.

CHARLES EDWIN ROI-IN.

